They used to pop up on ebay with some regularity. I sold one last year for somewhere between $100 and $150 if I recall correctly. Do a recurring search on ebay and I'd guess you'll find one withing a couple of months.

I think I still have one from the '87 I sold last year. It's in perfect condition; no faded bezel or hazy plexiglass; took it out when I installed perfect pass several years ago. If you're interested, PM me with with a reasonable offer and I'll try to dig it out of whatever box it's in.